1. Field of the Invention
The present invention is related to a sensor structure of a touch panel and a method of determining touch signal generating by the same, and particularly to a sensor structure of a touch panel having a single-layered sensor structure disposed on a surface of a substrate which is capable of determining the X coordinate and the Y coordinate of a touch.
2. Description of the Prior Art
In order to provide a friendly communication interface between users and computers, touch panels replace the conventional mouse and keyboard that users may interact with the touch panels by a finger or a stylus. The user selects or inputs data by contacting the touch panel, and the location where the user touches the panel is determined by a micro-processor, which calculates the location by processing the touch signal created by the touch on the surface of the touch panel.
Please refer to FIG. 1 and FIG. 2, which are schematic diagrams illustrating a conventional sensor structure 10 of a touch panel. FIG. 2 is a cross-sectional view of the sensor structure 10 taken along the line 2-2′ in FIG. 1. The sensor structure 10 has a first substrate 12, a second substrate 14 disposed under the first substrate 12, a plurality of Y-axis sensor lines 16 positioned between the first substrate 12 and the second substrate 14, and a plurality of X-axis sensor lines 18 disposed on a top surface of the first substrate 12. The sensor structure 10 has a plurality of first inputs/outputs 20 electrically connected to the respective X-axis sensor lines 18, and a plurality of second inputs/outputs 22 electrically connected to the respective Y-axis sensor lines 16. The first inputs/outputs 20 and the second inputs/outputs 22 are electrically connected to a control circuit (not shown). As shown in FIG. 2, the X-axis sensor lines 18 and the Y-axis sensor lines 16 are respectively disposed on the top surface and the bottom surface of the first substrate 12. When a user's finger touches the sensor structure 10, a change in the capacitance of the X-axis sensor lines 18 is generated and is used for determining the X coordinate of the position where the finger touches the sensor structure 10. In addition, a change in the capacitance of the Y-axis sensor lines 16 is generated and is used for determining the Y coordinate of the position where the finger touches the sensor structure 10. According to the capacitance changes in the X-axis sensor lines 18 and in the Y-axis sensor lines 16, the position where the finger touches the sensor structure 10 is confirmed. The sensor structure 10 is made by several processes to form the X-axis sensor lines 18 and the Y-axis sensor lines 16 respectively on the top surface and the bottom surface of the first substrate 12. The more manufacturing processes are performed, the higher the production cost and the higher the difficulties are. In addition, the first input/output 20 connecting to the X-axis sensor lines 18 and the second inputs/outputs 22 connecting to the Y-axis sensor lines 16 have to be formed extending from one end of the Y-axis sensor lines 16 and the X-axis sensor lines 18 which further increases the difficulty of circuit patterning. Therefore, the inputs/outputs of the conventional sensor structure 10 are formed along the X-axis and the Y-axis around the sensor structure 10.
Therefore, the present invention is provided in order to simplify the manufacturing process of the touch panel and to reduce the number of the inputs/outputs disposed around the touch panel.